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In an effort for further improvement of LSCF hollow fiber membrane properties in oxygen purification application, this work studied the use of polyethylene glycol (PEG) with different molecular weight of 2000, 3400 and 6000 Da as a pore former. A well-prepared hollow fiber membrane was successfully fabricated via extrusion followed by a sintering method. The results showed that the addition of PEG increased the viscosity of the dope suspension and formed a constant asymmetric pore configuration of the membrane after sintering at 1250 °C. The increasing molecular weight of PEG also leads to a decrease in the mechanical strength of the membranes, indicating that finger-like pores were sacrificed by forming irregular pores. The gas tightness was also examined under room temperature which showed that membrane with PEG 3400 achieved the best tightness with the nitrogen permeability of 3.55 × 10−5 mol·m−2·s−1·Pa−1. The oxygen permeation of the membranes was also influenced by the addition of PEG, where the highest oxygen permeation flux of 6.07 × 10−8 mol·cm−2·s−1 was obtained using a hollow fiber membrane with PEG 3400 due to the existence of the lowest dense layer thickness.

It is an inevitable trend of sustainable manufacturing to replace flood and dry machining with minimum quantity lubrication (MQL) technology. Nevertheless, for aeronautical difficult-to-machine materials, MQL couldn’t meet the high demand of cooling and lubrication due to high heat generation during machining. Nano-biolubricants, especially non-toxic carbon group nano-enhancers (CGNs) are used, can solve this technical bottleneck. However, the machining mechanisms under lubrication of CGNs are unclear at complex interface between tool and workpiece, which characterized by high temperature, pressure, and speed, limited its application in factories and necessitates in-depth understanding. To fill this gap, this study concentrates on the comprehensive quantitative assessment of tribological characteristics based on force, tool wear, chip, and surface integrity in titanium alloy and nickel alloy machining and attempts to answer mechanisms systematically. First, to establish evaluation standard, the cutting mechanisms and performance improvement behavior covering antifriction, antiwear, tool failure, material removal, and surface formation of MQL were revealed. Second, the unique film formation and lubrication behaviors of CGNs in MQL turning, milling, and grinding are concluded. The influence law of molecular structure and micromorphology of CGNs was also answered and optimized options were recommended by considering diverse boundary conditions. Finally, in view of CGNs limitations in MQL, the future development direction is proposed, which needs to be improved in thermal stability of lubricant, activity of CGNs, controllable atomization and transportation methods, and intelligent formation of processing technology solutions.

A significant drawback of the traditional photocatalysts such as titanium dioxide (TiO2) is their inability to absorb visible light from the solar spectrum due to their wide band gap energy. They are only photoactive in the ultraviolet (UV) region which is just a little fraction of the solar spectrum and could be harmful with much exposure to it. Due to its abundance in the solar spectrum, visible light needs to be harnessed for environmental applications. However, we lack visible light driven photocatalyst with long-lasting energy storage capacity for “round-the-clock photocatalytic” (RTCP) applications. For this reason, there is a growing need to find new photocatalysts that can mitigate these bottlenecks. It is evident from some carefully selected published articles (1976–2021) that tungsten oxide (WO3) and its composites have attracted popularity in recent years because of its outstanding properties and particularly its smaller band gap energy of 2.8 eV. However, pristine WO3 is limited due to relatively low energy density and smaller specific surface area. These drawbacks can be addressed by developing various WO3 – based materials to improve their performance. This paper reviews and discusses their recent development in surface advancement, morphology control, modification of nanostructured WO3 and its composites, and their RTCP energy storage for photocatalytic activities in visible light and the dark for environmental applications. Specific aspects focused on its nature, structure, properties, synthesis, coatings, deposition, approaches at modifying and enhancing its visible light photoactivity for enhanced performance and energy storage potential.

Sulfur and zinc substituted Co(OH)2 is synthesized by a simple co-precipitation one-step method followed by solvothermal treatment for oxygen evolution reaction. The high-resolution X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM) demonstrates that the Zn and S substitution significantly stabilizes the layered structure and causes an increase in the electron density around the Co center. The role of both cation and anion substitution is evaluated to enhance the oxygen evolution reactions. This enhanced activity is due to the in-situ oxidation of divalent Co into trivalent Co, and partially due to the stabilization of the layered structure, as highlighted by PXRD and TEM analysis, the gap between the layers is slightly reduced from 7.8 A to 7.5 A, for S–Zn–Co(OH)2. The in-situ conversion of Co2+ to Co3+ during electrocatalysis improved the OER electrocatalysis. The structural and physical characterizations are performed via XRD, EDX, SEM, TEM, XPS, AFM and BET.

Abstract: Physical vapor deposition (PVD) is a thin film fabrication process in the semiconductor industry. This review paper discusses the different types of PVD methods such as sputtering, cathodic arc deposition, pulsed laser deposition, and ion plating that could be employed in order to fabricate nanoscale thin films. This paper focuses on reviewing Zr-based nanoscale thin film properties, including the transformation of Zr to ZrO2 based nanofilms as high-k gate dielectrics. Additionally, its corrosion, mechanical and degradation resistance were thoroughly analysed. These properties are affected by gas flow rate changes, temperature, and crystallinity and are further discussed in each section. Thus, this review paper informs researchers of the thin films progress to date. Understanding the influence of PVD process parameters in fabricating Zr-based nanoscale thin film is vital for its long-term continuous improvement.

Kaolin has been found to be a more economical alternative in ceramic hollow membrane fabrication compared to alumina, silica, and zirconia despite having similar properties. However, it was discovered that apart from having high mechanical strength and the ability to withstand high operational temperature, the kaolin membrane has the tendency to dissolve in a high alkaline solution. Hence, in this study, zirconia (ZrO2) was imposed to kaolin suspension as co-starting material due to its stable hexagonal properties with kaolin to overcome this drawback. To study the dissolution property of the modified kaolin-based membrane, a phase inversion technique was used to fabricate zirconia-kaolin hollow fiber membrane (ZKHFM) followed by immersion in ammonium hydroxide (NH4OH) as an alkaline solution. Ammonia was aptly chosen for it being considered as one of the pollutants to be removed from wastewater. The mechanism, morphology and properties of the membrane were investigated in terms of sintering temperature, morphology, mechanical strength, pore size and porosity The results showed that ZKHFM with 10 wt% (ZK-10) with sintering temperature of 1,200 °C had the best performance in terms of having high mechanical strength (21MPa), excellent permeation flux (∼1,600 Lm2/h) and lowest dissolution (0.01 g dissolute) at pH 13, indicating the ability of ZKHFM to be used in alkaline solution.

In this article, visible-light-active binary metal doped Mn0.9Cu0.05Ag0.05O2 (MCAO) nanostructures were synthesized by a one-step co-precipitation method for superior antimicrobial and photocatalytic activities. For comparison, single metal doped Mn0.95Cu0.05O2 (MCO), Mn0.95Ag0.05O2 (MAO) nanostructures were also synthesized. Accompanied with the co-precipitation growth of the Cu and Ag in the MnO2 matrix, the binary metal doping not only influenced the crystal structure of MnO2, but also resulted in a remarkable improvement of the visible light activity and the prolonged separation of photoinduced carriers. The phase, morphology, and the chemical composition of the singly and binary doped MnO2 nanostructures were probed by reliable analytical methods, like PXRD (powder X-ray diffraction), FE-SEM (field emission scanning electron microscopy), and EDX (energy dispersive X-ray spectroscopy), respectively. Based on the assessment of the antibacterial and photocatalytic performance, it was observed that the Mn0.9Cu0.05Ag0.05O2 (MCAO) obtained a substantial improvement for different bacterial strains (S. aureus (G+), K. pneumonie (G-), and P. vulgaris (G-)) disinfection and methylene blue (MB) degradation under solar irradiation, which was ascribed to delayed charge recombination as well as effective generation of reactive species ( h + , O ‾ 2 · , and H O • ). These results revealed that the binary metal doping in a metal oxide matrix could provide a novel strategy for development of multifunctional nanomaterials.

In this work, waste cooking palm oil (WCPO)-based carbon nanotubes (CNTs) with encapsulated iron (Fe) nanoparticles have been successfully produced via modified thermal chemical vapor deposition method. Based on several characterizations, the dense WCPO-based CNT was produced with high purity of 89% and high crystallinity proven by low ID/IG ratio (0.43). Moreover, the ferromagnetic response of CNTs showed that the average coercivity and magnetization saturation were found to be 551.5 Oe and 13.4 emu/g, respectively. These produced WCPO-based CNTs were further used as heavy metal ions adsorbent for wastewater treatment application. Some optimizations, such as the effect of different adsorbent dosage, varied initial pH solution, and various heavy metal ions, were investigated. The adsorption studies showed that the optimum adsorbent dosage was 1.8 g/L when it was applied to 100 mg/L Cu (II) solution at neutral pH (pH 7). Further measurement then showed that high Cu (II) ion removal percentage (~80%) was achieved when it was applied at very acidic solution (pH 2). Last measurement confirmed that the produced WCPO-based CNTs successfully removed different heavy metal ions in the following order: Fe (II) > Zn (II) ≈ Cu (II) with the removal percentage in the range of 99.2 to 99.9%. The adsorption isotherm for Cu (II) was better fitted by Langmuir model with a correlation coefficient of 0.82751. WCPO-based CNTs can be a potential material to be applied as adsorbent in heavy metal ion removal.

This work investigates the effectiveness of ammoniacal nitrogen (NH 4 + -N) removal from contaminated water by adsorptive hollow fiber ceramic membrane (HFCM) derived from naturally made clinoptilolite. The technological value of this work is the simple mechanism of the adsorptive HFCM in removing gaseous ammonia in water by combining adsorption and separation. To test the technical feasibility of this proposed technology, clinoptilolite HFCM was fabricated via phase inversion-based extrusion/sintering technique and characterized by SEM and water permeation flux. The produced HFCM corresponds to the desired morphology of the asymmetric structure (dense and void formations) with outstanding adsorption performance of NH 4 + -N. The effects of the HFCM’s operational parameters on its removal are examined in terms of membrane dosage and isothermal studies. The adsorption isotherm behavior exhibited that the adsorption process fitted the Freundlich isotherm model with outstanding removal performance even at trace concentration of ammonia. The low amount used by HFCM (4.75×10−4m2) resulted in over 96% ammonia removal, indicating a low cost of adsorption process. The regeneration of saturated HFCM suggests an outstanding recovery of the HFCM for its subsequent use for NH 4 + -N removal. This study also reveals the potential of adsorptive HFCM as a simple and cost-effective technology for ammonia removal from wastewater.

Superhydrophobic membranes have great potential towards various application, especially for thermal-based membrane system such as membrane distillation. In this study, bioceramic hollow fibre membranes derived from cow bone waste were prepared by phase inversion/sintering method, followed by surface modification via immersion grafting with fluoroalkylsilane (FAS) agent. Interestingly, the grafting process led to the formation of hydroxyapatite nanorods, mimicking the unique structure of electrospun nanofiber membranes. The hydrophobicity of the modified membranes was assessed by measuring the water contact angle and showed excellent improvement from hydrophilic property to superhydrophobic with the highest value of 174° After the modification, the water entry pressure also improved from 0 to 1 bar. In addition, the presence of FAS agent on the membrane surface was observed using X-ray photoelectron spectroscopy (XPS). A correlation between pore size, porosity, and mechanical strength of the modified membrane was discussed; the increment of membrane pore size after grafting process is synonym to the dental erosion mechanism. The result indicates that the superhydrophobic bioceramic hollow fibre membranes derived from cow bone waste have significant potential to be developed for membrane distillation application in treating water and wastewater.

Heat dissipation is becoming more and more challenging with the preface of new electronic components having staggering heat generation levels. Present day solutions should have optimized outcomes with reference to the heat sink scenarios. The experimental and theoretical results for plate type heat sink based on mathematical models have been presented in the first part of the paper. Then the parametric optimization (topology optimization) of plate type heat sink using Levenberg-Marquardt technique employed in the COMSOL Multiphysics® software is discussed. Thermal resistance of heat sink is taken as objective function against the variable length in a predefined range. Single as well as multi-parametric optimization of plate type heat sink is reported in the context of pressure drop and air velocity (Reynolds number) inside the tunnel. The results reported are compared with the numerical modeled data and experimental investigation to establish the conformity of results for applied usage. Mutual reimbursements of greater heat dissipation with minimum flow rates are confidently achievable through balanced, heat sink geometry as evident by the presented simulation outcome. About 12% enhancement in pressure drop and up to 51% improvement in thermal resistance is reported for the optimized plate fin heat sink as per data manifested.

The nickel oxide (NiO) nanosheet/nanoflower-like (NS/NF) films-based humidity sensors doped with zinc (Zn) and without doping were successfully deposited on the NiO seed layer-coated glass substrates using the immersion method. The addition of 1 atomic percent of Zn concentration into pristine NiO has a significant influence on the structural and morphological properties as well as humidity sensing performance as there are changes in its crystal parameters. The Zn doping increased the dislocation density and tensile strain but shrank the average crystallite size (D) of NiO. The average D was estimated from three X-ray diffraction peaks of undoped and Zn-doped NiO NS/NF films, and the calculated values are 16.3 and 12.3 nm, respectively. The NiO surface morphology and the thickness are also affected by the Zn doping. The nanoflower (NF) shape and pattern on the nanosheet (NS) layer disappeared and dispersed obviously. Meanwhile, the NS thickness sharply decreased from 910 to 410 nm. By using silver contact as a sensing measurement electrode, the sensitivity of the Zn-doped NiO-based humidity sensor is increased to 78 compared to undoped NiO with a sensitivity of 30.

Despite the wide applications of multi-effect vapor absorption systems, their energy requirement is relatively higher. Also, their exergy analyses found in the literature reveal that the exergy destruction rate at the absorber is quite significant and has the potential for improvement in its energy efficiency. In this work, the exergy destruction rate at the absorber is minimized using the penalty factor method against the optimized generator temperature of the double-effect vapor absorption system by considering absorber, evaporator, and condenser temperatures into consideration. Modeling of the double-effect vapor absorption system was performed using a thermodynamic toolbox in SIMULINK. The present model employed a refrigerant heat exchanger to enhance the system cooling capacity. The Liquid-vapor ejector valve at the absorber also improved the mixing of the solution and refrigerant vapor resulting in lower irreversibility of the system. Results show that the coefficient of a performance increase by 2.4 % with refrigerant heat exchanger and exergy loss at absorber decrease by 9.4 % with ejector. The optimum performance was seen at the condenser and evaporator temperatures of 308.8 K and 278.1 K, respectively with an 8.2 % improvement in exergetic efficiency. Finally, it is concluded that the multi-effect absorption system shows better performance by minimizing the irreversibility.

The simulation-based artificial neural networks (ANN) program is one of the suitable candidates from artificial intelligence simulation which can work to predict important ultrasonic and mechanical parameters in the glass field. This research is focused on exploring the validity of this system by comparing the prediction values from ANN with the experimental measurements and other theoretical models. The ANN simulation was effectively applied to a binary zinc-borate glass system with the composition of zZnO−(100-z)B2O3 where z = 0, 40, 45, 50, 55, and 60 mol%, which was fabricated by using the melt-quenching techniques. The increase of ZnO content caused the ultrasonic velocity and elastic moduli of the glasses to exhibit a decreasing trend. The bond compression theoretical calculation compared with the experimental measurement was considered to be satisfactory with the value of the coefficient R2 being around 0.92452 to 0.98492. The Makishima-Mackenzie calculation model concerning the experimental measurement of the elastic moduli and Poisson's ratio were between 0.86628 to 0.99786. The coefficient R2 value from the ANN simulation displayed on the density, ultrasonic velocity, and elastic moduli graph is around 0.9999 to 1.0000, which is considered to be very reasonable. The values predicted by this remarkable model proved that ANN simulation is suitable for use in glass research.

Background Unlimited energy demand and rapid urbane development are major deriving forces to generate bioelectricity through microbial fuel cells (MFCs) and have been a hot area for 2-decades. Various advancements have been employed to improve the MFC's efficiency through electrode and membrane materials. Methods Here, we discussed the recent innovations and developments to fabricate the electrode and membrane materials, which play a key role in bio-energy production and performance. Specifically, the morphological aspects, including pure/doped carbon-based electrodes and their large surface area, directly enhanced the oxygen reduction efficiency of MFCs. Findings The impact of organic and inorganic hybrid composite bio-polymer membranes and separators to improve the electron transfer ability and remedies for associated biofouling problems are also highlighted. Numerous enhancements to the material's physical, mechanical, and chemical properties are explored in detail to prevent biofouling issues. In addition, it highlights how the well-ordered mesopores, large surface area, and biocompatibility of MFCs directly affect their stability and performance. Finally, this review article introduces current issues with smart, feasible solutions, stability improvements, and future perspectives of MFCs and critically evaluated recent progress and developments in MFCs technology which can be useful for academic and industrial researchers.

The present study evaluated the effect of silicon (Si) seed priming and sulfur (S) foliar spray on drought tolerance of two contrasting maize hybrids viz. drought tolerant Hi-Corn 11 and susceptible P-1574. The maize seeds were primed with (3 mM Na2SiO3) or without Si (hydropriming) and later sown in pots filled with sandy loam soil. Drought stress (25–30% water holding capacity or WHC) was initiated at cob development stage (V5) for two weeks, whereas the well-watered plants were grown at 65–70% WHC. On appearance of drought symptoms, foliar spray of S was done using 0.5% and 1.0% (NH4)2SO4, whereas water spray was used as a control. The drought-stressed plants were grown for further two weeks at 25–30% WHC before the final harvest. The results showed a marked effect of Si seed priming and foliar S spray on biomass, physiological and enzymatic processes as well as macronutrient concentrations of maize. In comparison to control, the highest increase in leaf relative water content (25%), chlorophyll a content (56%), carotenoids (26%), photosynthetic rate (64%), stomatal conductance (56%) and intercellular CO2 concentration (48%) was observed by Si seed priming + S foliar spray (Si + S) under water deficit conditions. Also, Si + S application stimulated the activity of catalase (45%), guaiacol peroxidase (38%) and superoxide dismutase (55%), and improved NPK concentrations (40–63%) under water limitations. Our results suggest that Si seed priming + foliar spray of S is more effective than the individual application of these nutrients to enhance drought tolerance in maize.

The Fermi level alignment between electrodes and two-dimensional (2D) materials is significant in characterizing sensors based on their reversibility, response time, sensitivity, and long-term stability. Here, we have demonstrated that the modulation of the Schottky barrier height between the interface of metal (Pd/Au) and multilayered ReSe2 nanoflakes caused the change in the transfer curve (Ids-Vbg) of FETs based devices and rectifying characteristics (Ids-Vds) of the Schottky diodes at various hydrogen concentrations at T = 22 °C, fluctuating from 50 to 350 ppm with a response (R%) from 669 to 1198%, respectively. Sensors based on a mono- or bilayer system did not exhibit sensitivity to hydrogen gas owing to metal electrodes diffused into materials. The value of the ideality factor of the Schottky diode-based sensor changed from 4 to 1.6 as the hydrogen concentration was changed from 50 to 900 ppm, while the relative response increased from 0 to 3.5 as the hydrogen concentration was increased from 0 to 900 ppm. This research can offer a real solution for developing cost-effective, faster, and room temperature sensors based on 2D materials.

In this paper, a mathematical model of the blade coating of the viscoelastic Carreau fluid which passes through the gap between the fixed blade and the moving substrate is constructed. The governing equations in the light of LAT (Lubrication Approximation Theory) are nondimensionalized and the solutions for the velocity, volumetric flow rate and the pressure gradient are calculated using Adomian decomposition method and numerical method. Numerical results for the velocity distribution using shooting method have also been studied by taking the full lubrication equation without taking the binomial expansion. Some important quantities from the industrial point of view like pressure, shear stress, Nusselt number and skin friction coefficient are also calculated. The important results are graphically shown at the end. With exponential blade coater, we have calculated velocity profiles, pressure, coating thickness and blade loading. Some of these results are shown graphically while other are presented in the tabulated form.

Super hydrophobic wavy mini channel heat sink is analyzed experimentally for thermal and hydraulic analysis using SiO2 and TiO2 aqueous nanofluids with volumetric concentration of 0.01% and 0.02%. ...

These days, numerous decisions and efforts are contributing to cerebral palsy (CP) cases. Patient with spastic or dyskinetic CP has to survive independently, where most of the time is spent in a wheelchair. An extension headrest must be applied to maximize independence and functionality in the sitting position for routine activities. This study aims to investigate the effects of material selection in fabricating the 3D-printed adjustable headrest. Expected headrest users would be children (age seven to nine years old). There are five materials in this research: Polycarbonate (PC), Polylactic Acid (PLA), Acrylonitrile Butadiene Styrene (ABS), Polyamide (Nylon), and Polyethylene Terephthalate (PETG). In the designing process, Computer-Aided Design (CAD) software focuses on designing the structure and Finite Element Analysis (FEA) software to analyze various parts. To conclude this study, PLA is chosen as the best material based on the best stress, deformation, and safety factors. Keywords-- Adjustable headrest; finite element analysis; material selection; 3D printing

In recent years, it has been shown that high pressurized solidification has been impeding cooling rate measurement in semisolid forging of aluminum alloys. This has restricted the establishment of ...

The current paper examines the effects of zinc oxide nanostructure configurations, as photo-anode formations of organic solar cells, on the performance of power conversion. To this end, some experiments were conducted during which a near band edge emission red shift of ~ 0.11 eV from nanoparticles to vertically oriented nano-rods was observed. This bandgap narrowing promotes transferring of photo-excited electrons towards the conduction band of photo-anode. A ~ 48% decrease in the deep level emission intensity revealed a smaller non-radiative waves emission due to lower level of crystal disorder. Using vertically oriented zinc oxide nanorods as photo-anodes, the photovoltaic efficiency of the organic solar cell improved considerably. The nano-rod-structured photo-anodes showed a 0.22 V rise in the open-circuit voltage, from 0.76 to 0.98 V, and a 2.08 times increment in the overall conversion performance, compared to the zinc oxide nanoparticle-structured photo-anodes. This superior performance is attributed to a greater chance of charge recombination and light-trapping in the cells, more efficient light absorption, and high level of crystallinity that grants easier electron mobility for vertically oriented zinc oxide nanorods. Moreover, a lower charge-transfer resistance (0.85 Ω) was achieved due to better electro-catalytic action for oxygen reduction for vertical nanorods compared to the other two zinc oxide configurations (1.62 Ω and 4.06 Ω). This boosted the cell performance by increasing the short-circuit current density (JSC). The fabricated solar cell may contribute to sustainable and environmentally friendly electricity generation process through reducing the consumption of non-renewable energy sources.

Aim and objective To evaluate the effect of cervical margin relocation (CMR) for crowns designed using CAD/CAM technology and fabricated from lithium disilicate (e.max, CAD) before and after aging; and to compare the fracture forces and failure type of the tested crowns. Materials and methods Mesio-occluso-distal(MOD) cavities 1 mm above the cementoenamel junction(CEJ) were prepared on 40 maxillary first premolars. The teeth were divided into four groups. In group A, all cervical margins (CM) were located 1 mm above the CEJ. However, in both mesial and distal proximal boxes of groups B, C, and D, in addition to the MOD cavities, the CMs were extended 2 mm on both sides below the CEJ apically to simulate the CMR technique. In group B, the mesial and distal proximal boxes were filled with flowable composite, while for group C and group D, specimens were filled with composite resin fillings. To simulate the CMR technique, the cavities were filled with composite layers of 3 mm in two increments. Using the CAD/CAM system, 40 standard crowns were prepared on premolars, then cemented using a dual-curing adhesive cement. Assessments of the marginal integrity of interfaces of the proximal boxes of the cemented crowned teeth were recorded. Statistical differences between groups were analyzed using the ANOVA and Bonferroni's posthoc test. Results The first null hypothesis was accepted since no statistically significant differences were found in marginal integrity before and after aging (p>0.05), while the second was partially rejected since different fractured force values were recorded and a significant difference was detected between group D and group B. The third hypothesis was rejected because the catastrophic fracture rate was the highest among the four groups. Conclusion The implementation of CMR before and after aging had a good effect on the marginal integrity of CM relocation. The CMR technique with resin luting cement of lithium disilicate crowns is effective and recommended for the restoration in deep proximal boxes of premolars or posterior teeth. Clinical significance CAD/CAM-generated e. max all-ceramic crowns with composite as the CMR enable the reconstruction of severely destroyed teeth irrespective of the position of the cavity margins.

Tremendous development in electronic devices and their indiscriminate use has created a severe problem of electromagnetic pollution. Different types of electromagnetic interference (EMI) shielding materials and structures are used to protect electronic devices from the harmful effect of electromagnetic pollution. A present study was conducted to compare the effect of dielectric and magnetic nanofillers on electromagnetic shielding effectiveness (EMI SE) of carbon fiber reinforced composite structures (CFRC). Composites structures were developed using different dielectric and magnetic nanofillers. Effect of nanofillers on microwave absorption properties and reduction in electromagnetic pollution was investigated. Relationship between electrical conductivity and EMI shielding effectiveness in L, S, C, and X-frequency range was also studied. Among the dielectric nanofillers, silicon carbide showed excellent EMI SE in X-frequency range, while among magnetic nanofillers, zinc oxide showed excellent EMI shielding characteristics in a broad frequency range of 100 MHz to 13.6 GHz. Among magnetic nanofillers, CFRC with zinc oxide nanofillers showed the lowest skin depth value of 3.32 × 10−4 mm and among dielectric nanofiller, CFRC with silicon carbide nanofillers gave the lowest skin depth value of 6.49 × 10−4 mm, implying their excellent potential in EMI shielding applications.

Natural polysaccharides and their designed structures are extremely valuable due to their intrinsic pharmacological properties and are also used as pharmaceutical aids. These naturally occurring polysaccharides (e.g., psyllium and alginate) are gaining popularity for their use in the preparation of interpenetrating polymer network (IPN) materials with improved swelling ability, biodegradability, stability, non-cytotoxic, biocompatibility, and cost-effectiveness. IPN is prepared sequentially or simultaneously by microwave irradiation, casting evaporation, emulsification cross-linking, miniemulsion/inverse miniemulsion technique, and radiation polymerization methods. In addition, the prepared IPNs have has been extensively characterized using various analytical and imaging techniques before sustainable deployment for multiple applications. Regardless of these multi-characteristic attributes, the current literature lacks a detailed overview of the biomedical aspects of psyllium, alginate, and their engineered IPN structures. Herein, we highlight the unique synthesis, structural, and biomedical considerations of psyllium, alginate, and engineered IPN structures. In this review, a wide range of biomedical applications, such as role as a drug carrier for sustain delivery, wound dressing, tissue engineering, and related miscellaneous application of psyllium, alginate, and their IPN structures described with appropriate examples. Further research will be carried out for the development of IPN using psyllium and alginate, which will be a smart and active carrier for drugs used in the treatment of life-threatening diseases due to their inherent pharmacological potential such as hypoglycemic, immunomodulatory, antineoplastic, and antimicrobial.

Biological compact bone tissue is a typical hard-brittle material, which is extremely sensitive to high temperature. For the calculation of bone microgrinding temperature field, most of the known methods are based on the constant heat flux of the average tangential force without considering the ductile grinding characteristics of bone, leading to large calculation error. A semiempirical heat flux theoretical model based on the dynamic grinding force of hard-brittle bone ductile microgrinding is proposed to solve this bottleneck problem. The mechanism of heat generation and consumption in microgrinding zone under ductile removal mode of bone material is studied first, and the probability statistics of effective cutting abrasive number is analyzed. The heat distribution coefficient in grinding zone is calculated, and the semiempirical heat flux model of the ductile removal of hard-brittle biobone material is developed. Microgrinding experiments are conducted to verify the effectiveness of ductile removal grinding heat flux model. The temperatures of different measuring points on the surface of bone samples and micro grinding force are measured. Results show that the theoretical calculation is consistent with the experimental results, with an average error of

The recent advancement in the nanotechnological sector has evidently revolutionized the biotech- and biomed-divisions of the twenty-first century. Accordingly, designing and fabrication of robust materials, for instance nanodiamonds (NDs), at the micro- and nano-scale with unique structural, physiochemical, and functional features have been the focus of technological investment and are becoming popular in different areas of science. Particularly, NDs among various nanomaterials are of supreme interest with significant market value due to their unique structural fabrication, ease in surface modification, minimal/no toxicity, biocompatibility, facile biodegradation and/or safer exit upon administration safety, patient compliance, and smart action. Therefore, the interest to deploy NDs in many applications is on the rise over the past few years. Though a plethora of literature is available on the NDs, but in a scattered manner. Thus, this work is an effort to spotlight the detailed surface chemistry and comprehensive coverage of biotech- and biomed-applications of NDs, at a single venue. Considering the above critics, herein, we reviewed state-of-the-art NDs as a smart and sophisticated platform – namely as a nanotechnological strategy to construct and deploy high-end products to withstand the biotechnological and biomedical sectors of the modern world. Following a brief introductory statement of problems and opportunities, structural and functional entities of NDs with reference to their surface chemistry are given with examples. The latter half is focused on the NDs applications in catalysis, sensing, separation, drug delivery, gene delivery, and cosmeceutical formulations. Finally, an overview is also given on the NDs-assisted products in the market, along with research gaps and future trends in NDs research are also included in this review.

Noble metal dichalcogenides (NMDs) are two-dimensional (2D) layered materials that exhibit outstanding thickness-dependent tunable-bandgaps that can be suitable for various optoelectronic applications. Here, we developed high-performance switching photodiodes based on mix-dimensional 2D palladium diselenide (PdSe2) and three-dimensional (3D) silicon (Si) heterojunctions with a broadband spectral response by a mechanical exfoliation technique. We studied the gate-tunable rectifying behavior of n-PdSe2/p-Si diodes employing an ionic liquid gate and achieved a maximum diode rectification ratio If/Ir up to ∼1.0 × 105 with the lowest value of ideality factor ∼1.22 (at Vtg = −2 V). At different temperatures (60 to 300 K), Zener tunneling and avalanche breakdown phenomena were detected at the junction of PdSe2–Si. These devices showed excellent self-driven photoresponses over broadband wavelengths from 400 to 1200 nm. The response speed of estimated is 9.2/17.3 μs, which represents a fast photoresponse. Moreover, in our devices, open-circuit voltage (VOC = 0.6 V) switching behavior is attained with the on/off state of the incident light. Moreover, these devices were attested for dynamic rectification, and this effectively rectified an input alternating-voltage sine wave signal to an output signal. The results of this study indicate that 2D PdSe2 can be employed for high-performance optoelectronic applications.

In this work, sand/zinc oxide (ZnO)/titanium dioxide (TiO2)-based photocatalysts were hybridized with graphene oxide (GO) and GO_multi-walled carbon nanotubes (MWCNTs) hybrid solution. The novel hybrid was then used in photocatalysis to degrade dye contamination. The nanocomposite photocatalyst was initially fabricated by growing ZnO nanorods (NRs) via sol-gel immersion followed by synthesizing TiO2 NRs for different times (5 and 20 h) using a hydrothermal method on sand as a substrate. Prior to the hybridization, the initial GO was synthesized using electrochemical exfoliation and further mixed with 1 wt% MWCNTs to form GO_MWCNTs hybrid solution. The synthesized GO and GO_MWCNTs hybrid solution were then incorporated onto sand/ZnO/TiO2 nanocomposite-based photocatalysts through immersion. Various sand/ZnO/TiO2-based photocatalysts were then tested for methylene blue (MB) dye degradation within 3 days. On the basis of UV-Vis measurement, the highest MB degradation was achieved by using sand/ZnO NRs/TiO2 NRs (5 h)/GO_MWCNTs (92.60%). The high surface area and high electrical conductivity of GO_MWCNTs prolonged the lifetime of electron/hole separation and thus enhanced the photocatalytic performance.

To meet the food demand of the increasing world population, use of insecticides is increasing day by day. However, intensive application of insecticides has increased the health risks to the human. Therefore, sustainable alternatives with a limited or no harm to the human and environment are always preferable. A study was conducted to determine the effect of rice husk biochar (RHB) on brinjal growth, mineral nutrients and insect infestations. The soil filled pots (7 kg pot−1) were amended with various levels of rice husk biochar (Control, RHB 3.5, RHB 7, RHB 14, RHB 21 and RHB 28 g pot−1) and its effects were determined on brinjal plant. Rice biochar (RHB 28 g pot−1) amended plant produced maximum biomass. Further, results also showed that higher doses of RHB significantly lower the insect infestation. Biochar treatment has also improved the plant mineral nutrients especially silicon (Si) concentration in the leaves. Hence, it is concluded that RHB tends to reduce insect infestation on brinjal plants by improving Si uptake and it may provide a strategy to sustain brinjal production. However, further studies must be carried out for comparative efficacy of the RHB with insecticide in deterring insect infestation for its widespread recommendations.

As an emerging member of the colloidal semiconductor quantum dot materials family, intraband quantum dots are being extensively studied for thermal infrared sensing applications. High-performance detectors can be realized using a traditional p-n junction device design; however, the heavily doped nature of intraband quantum dots presents a new challenge in realizing diode devices. In this work, we utilize a trait uniquely available in a colloidal quantum dot material system to overcome this challenge: the ability to blend two different types of quantum dots to control the electrical property of the resulting film. We report on the preparation of binary mixture films containing midwavelength infrared Ag2Se intraband quantum dots and the fabrication of p-n heterojunction diodes with strong rectifying characteristics. The peak specific detectivity at 4.5 μm was measured to be 107 Jones at room temperature, which is an orders of magnitude improvement compared to the previous generation of intraband quantum dot detectors.

Nanofluids are advanced class of heat transfer fluids that are in trend due to their high thermophysical properties over the past two decades. However, there are some limitations and restrictions t...

Transition metal impurities such as chromium (Cr) and vanadium (V) in solution deteriorate electrical conductivity of smelter grade aluminium (Al). These impurities can be removed from solution via boron treatment in which borides form upon their in-situ reaction with boron (B)-bearing substances. However, Cr removal from smelter grade Al solution is not well understood. A disagreement related to chromium boride (CrB2) formation in molten Al in the presence of other transition metals (V, Ti, Zr, Fe) by adding Al–B master alloy has been reported in literatures. This study presents an effort to understand the mechanism of Cr removal from Al–0.50%Cr–0.50%V (mass fraction) alloy by adding Al–B (AlB12) master alloy at 1023 K in the Al alloy solution. Results indicate that Cr removal from molten Al–0.50%Cr–0.50%V alloy by forming stable borides cannot be achieved at 1023 K; whereas excess of B in the solution preferentially forms aluminium boride (AlB2) over CrB2 during boron treatment of molten Al. The underlying kinetics of V removal from molten Al–0.50%Cr–0.50%V alloy revealed that early reaction stage is controlled by [B]/[V] mass transfer through liquid phase and mass transfer coefficient (km) was measured to be 9.6×10−4 m/s. The later reaction stage was controlled by [B]/[V] diffusion through boride (VB2) ring. This study, therefore, advocates to investigate alternative ways to remove Cr from molten Al.

We have demonstrated the fabrication of Zn2GeO4 nanostructures based SERS substrates and their potential application for the rapid detection of different pathogens. The SERS substrates were grown by a very simple and cheap route using vacuum tube furnace. The structure and morphology of grown SERS substrates were modulated by annealing the samples at different temperatures ranging from 600 °C to 900 °C. E.Coli and MB solutions were placed on the grown SERS substrate and investigated using Micro Raman Mapping System with 633 nm Laser having power 0.75 mW with exposure time of 2s. Raman data demonstrated that SERS substrate which was annealed at 800 °C showed highest enhancement factor of 7.9 × 102 MB signal. Similar enhancement of Raman signal for E. coli was also observed. The strongest Raman signal of E.Coli and MB for SERS substrate which was annealed at 800 °C is due the fact this sample has nanostructure morphology which resulted in the enhancement of Raman signal. Successful identification of E. coli and MB showed the capability of Zn2GeO4 nanostructures to be used for the detection of pathogens.

A low-cost hydrophobic mullite hollow fibre membrane (Hy-MHFM) fabricated via phase inversion/sintering technique followed by fluoroalkyl silane (FAS) grafting is presented in this study. The prepared CHFMs were characterized before and after the grafting step using different characterization techniques. The pore size of the CHFM surface was also determined using ImageJ software. The desalination performance of the grafted membrane was evaluated in direct contact membrane distillation (DCMD) using synthetic seawater of varying salt concentrations for 2 h at various feedwater temperatures. The outcome of the evaluations showed declines in the permeate flux of the membrane at increasing feed concentration, as well as increased flux with increased feed temperature. The long-term stability of the membrane was achieved at time 20 h, feed temperature 60 °C, and permeate temperature 10 °C, the membrane achieved a salt rejection performance of about 99.99 % and a water flux value of 22.51 kg/ m2 h.

Lung cancer is the most common type of cancer, being the leading cause of death worldwide. Several efforts for the prevention and treatment have been made to suppress the growth of lung cancer. In this context, hydroxyapatite (HAp) nanoparticles have potential to induce apoptosis in cancer cells and, therefore, can be used for the treatment of cancer. The combination of HAp nanoparticles with a drug loader such as zirconium (Zr) is expected to improve the efficacy of HAp nanoparticles in lung cancer treatment. In this study, Zr doped hydroxyapatite (HAp-Zr) nanoparticles were designed for lung cancer therapy. HAp-Zr nanoparticles were prepared by doping the HAp nanoparticles with Zr. The cytotoxic assay to the cancer cell of HAp-Zr nanoparticles was determined in the lung cancer cell line A549. The nanoparticles were labeled using Scandium-46 radioisotope ([46Sc]Sc-HAp-Zr) to evaluate the cellular uptake and biodistribution studies. The results showed that the [46Sc]Sc-HAp-Zr nanoparticles were accumulated in the lung cancer cell line A549, and Zr doped increased the cellular internalization. The cytotoxic assay showed that the IC50 value of the HAp-Zr nanoparticles was 513 μg/mL. In the biodistribution studies on normal mice, the radiolabeled [46Sc]Sc-HAp-Zr showed a high accumulation in the liver as an excreted organ and in the lungs as the target organ. Taken together, these findings suggest that HAp-Zr nanoparticles have the potential to be used as drug candidate for the treatment of lung cancer.

Introduction: Orthopaedic injuries involving the olecranon are among the most often encountered in the emergency department. Objective: To determine the functional outcomes of displaced olecranon fracture fixed with intermedullary partially threaded screw augmented with tension band wiring Material and methods: This Descriptive/multicentric case series was conducted in Department of Orthopedics, Bahawal Victoria Hospital/Civil (Sadiq Abbasi) Hospital, Bahawalpur during June 2019 to June 2021. Patients who came through the emergency department and met the inclusion criteria were enrolled and given informed permission after clearance from the hospital's ethics committee. During general anesthesia or a biere’s block, all patients received tension band wire and intramedullary screw fixation. Results: Functional outcomes of displaced olecranon fracture fixed with intermedullary partially threaded screw augmented with tension band wiring was recorded as excellent in 57.39%(n=66), 32.17%(n=37) had good outcome, 10.44%(n=12) had fair outcome. Conclusion: We concluded that that functional outcomes of displaced olecranon fracture fixed with intermedullary partially threaded screw augmented with tension band wiring is good; however, validation is required through other local studies. Key words: Olecranon fracture, Intramedullary partially threaded screw, Tension band wiring, and Campbell’s posterolateral approach